Doc modding Marantz imperial 7

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Thinking about speaker stands today. I have a separate thread in general audio about it as some may not look here.

I did a mock up of a single leg stand made with a 50 mm solid round brass bar. It's heavy :dance:

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I really like the look of a substantially wide diameter single leg but will consider a different amount of legs if necessary.

Had a look around the farm today to look for inspiration as to what to use for a base. Plenty of 50mm thick concrete slabs to cut up in to 30 cm2 bases. But would they look better if the bases had a slightly bigger footprint than the speaker cabs ? Don't know until I do a rough mock up.

Anyway, I found some of these knocking about from an old set of Cambridge rollers. :dance:

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Heavy as fook as they are made of solid steel and with the added plus of having a round hub in the centre where the axle used to go. I remember using these when I was teenager to roll down the seed bed after drilling cereals. Times have moved on since. The axle is long gone as I can't find it but was probably worn down anyway after many decades of use.

A 50 mm solid brass round bar fits in there but is about 4 mm too small so a bit of a bodge is required to pack the gap to make it a really tight fit.

This 58 mm brass bar is slightly too big but you get the idea

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A longer 50 mm brass bar in this pic

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The only thing is that these roller rings are a little bit wider than I would like at 49 cm so will be sticking out about 9 cm at each side of the speaker. I like the fact that they are recycled and will look good when cleaned and painted. Maybe too rustic or industrial looking ? They certainly will be heavy combined with the brass bar and very sturdy.

Any body got any thoughts ? Your views are much appreciated.
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Ordinaryman (Mon Jan 11, 2021 2:29 pm)
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Re: Doc modding Marantz imperial 7

Unread post by Ordinaryman »

I think they would be great and the fact that the footprint is wider would be a bonus, if kids are likely to be around ;)
Less conventional like the speakers 8-)
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karatestu (Mon Jan 11, 2021 2:42 pm)

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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

A proper mock up of what a 30 cm cube would look like on a stand using a Cambridge roller ring for a base, a 50 mm diameter solid round brass bar leg and a 30 cm2 aluminum top plate. I would use a 6 mm thick aluminum top plate rather than the bit I have used for the mock up.

Here is a cube in it's native wild habitat. Yes, I know I need to sweep the leaves :roll:

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Opinions much appreciated. I suppose I should be showing my wife as well :roll:
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Ordinaryman (Mon Jan 11, 2021 3:37 pm) • Toontrev (Wed Jan 13, 2021 10:24 am)
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Re: Doc modding Marantz imperial 7

Unread post by Ordinaryman »

Spot on :clap: imo . Don't think they would have much wife appeal? mind you I don't know your wife but from what I've seen of your posts she seems very tolerant :shock:
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karatestu (Mon Jan 11, 2021 3:52 pm)

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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Ordinaryman wrote: Mon Jan 11, 2021 3:45 pm Spot on :clap: imo . Don't think they would have much wife appeal? mind you I don't know your wife but from what I've seen of your posts she seems very tolerant :shock:
Thanks, I think :think: Wife is very tolerant but there is a limit like with everything :lol: She has only seen one of my creations and that is these little 30cm cubes. A while ago I mentioned my speakers were going to be floor standers of 30cm x 30cm x90cm. A got a reaction like "whatever, as long as we can all enjoy them". Plans have since changed obviously.

I like the look of that mock up as I can see past the roughness of what it look like now to the finished article. I am not adverse to doing something completely different though.

Paul mentions he likes open frame style stands with four legs, no hollow legs and low mass (not metal). I don't really know what I like to be honest as I haven't tried much. Currently my speakers are resting on three legs 40 cm long made out of 3" square fence posts :lol: Can't think of anything bad to say about the sound. Certainly sounds better than the two pairs of hollow metal stands (two under each speaker).

I have loads of small diameter brass and stainless steel solid round bar that would be a much lighter affair, 15 mm, 18 mm, 28 mm diameters. And I have more than enough in those smaller diameters to do four legs for each stand. But then it would look quite conventional.

Don't know what to do for the best really :violin:
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Ordinaryman (Mon Jan 11, 2021 4:26 pm)
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Re: Doc modding Marantz imperial 7

Unread post by Ordinaryman »

Whilst I think they look great and different, I have to say I agree with a lot that savvy said. I have 3 different sets of stands acquired over many years and the best sounding with all of the speakers that I have used/use are open framed with 4 legs. Mine are hollow but filled with expanding foam many years ago, Target I think? Having said that they are to low for my cubetts got some atacams for them.
I just think you have the stuff sitting around and the ability to put it to good use. Like always you might just surprise yourself and others if you have the time. Big plus, for us maybe not you, the pleasure of reading your posts :epopc:
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karatestu (Mon Jan 11, 2021 5:12 pm)

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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Yesterday I ordered a pair of these polystone (resin mixed with stone) planters.

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30 cm cubes in black. I mentioned them weeks ago and was sick of procrastination so ordered a pair. If they arrive in one piece, look good and pass the knuckle rap test :lol: then I will use them for my cabinets. If they are not up to scratch then I have a couple of garden planters :lol: :lol: :lol:

If they do turn out to be suitable then I will need to make a baffle for the open side. I do not know what the underside of them look like because there are no pictures of the bottom. That might need a matching baffle over the top of it depending on whether it is flat and finished properly. No hardship if I have to make two identical baffles, at least it will be symmetrical (which satisfies my OCD).

Internal volume is 22 Litres and given that the outside dimensions are all 30 cm I calculate that the walls of the cube are 10 mm thick. They are made of resin and stone particles so I expect the walls to be stiff and strong. If that is the case I will probably not be steel lining them although might if I think it will be beneficial.

Cutting a round hole in the bottom of the pot is the only fly in the ointment as it might require a diamond core hole cutter. But then if I am putting another baffle over the top of it I could cut a square one with my circular saw with diamond blade and it won't be seen :dance:
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Re: Doc modding Marantz imperial 7

Unread post by Latteman »

If they are double skinned u could fill them then reinforce
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Re: Doc modding Marantz imperial 7

Unread post by Latteman »

Saw these and thought of you
https://www.ebay.co.uk/itm/363032224714
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karatestu (Wed Jan 13, 2021 10:22 am)
Analogue Source -
Denon DP47f- Ortofon mc20 supreme
Ifi Zen Phono
Doug Self balanced Pre amp
Akai 4000DS mk2 R2R
Digital Sources- IfI stream, Ifi Neo idsd Dac; Tidal / Radio Paradise
Amplification Nva 30vdc mono blocks
Speakers Lii Audio F-15 in Open Baffle; Ls6
Weiduka AC8.8- for digital sources
Mini BMU for analog sources

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Nice find Peter. I need 0.82 uf though :( You can't get that value in the Russian PIO's I use so eventually I will have to use something else :roll:
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